GENEVA — The resolution passed by the United Nations’ top human rights body on Friday seemed innocuous, if obscurely worded in places.

Without specifying any immediate action, it called for “a community of shared future for human beings” and “mutually beneficial cooperation in the field of human rights” — words reflecting “the very purpose of the United Nations,” according to Yu Jianhua, ambassador for China, whose initiative it was.

Western officials and rights organizations, however, saw another purpose at work. They share deep concern about the wider intent behind those phrases, seeing them as tools in a developing effort to reshape international norms on rights and make the world a safer place for autocrats.

For most of the decade since the body, the Human Rights Council, became active, China’s posture at its meetings has tended to be defensive, fending off criticism of its suppression of dissent and voting against initiatives to monitor or censure abuses by other states. Not any more: This was the second resolution it has brought forward at the council in the past nine months.

“This is China stepping out of the shadows to play a more assertive role and to use its increasing leverage globally to get what it wants,” said Ted Piccone, a senior fellow at the Brookings Institution.

Only the United States voted against the latest proposal at the 47-member council, though 17 other countries abstained. Several of those, including Japan, Australia and Switzerland, criticized the initiative.

“Cooperation is the essence of our time, which calls for mutual benefits to realize the goal of human rights for all,” Mr. Yu told the council, adding: “We live on the same earth, we face common challenges.”

“It is clear that China is attempting through this resolution to weaken the U.N. human rights system and the norms underpinning it,” countered Jason Mack, a senior United States diplomat.

The earlier Chinese resolution, passed by the council in June, promoted in similar language the key contribution of development “to the enjoyment of all human rights.” The People’s Daily, the voice of the Communist Party, celebrated its adoption as a setback to the West’s monopoly on rights and “a major shift in the global human rights conversation.”

The resolution adopted on Friday appeared to double down on that objective. The first draft circulated by Chinese diplomats echoed language from the speeches of President Xi Jinping, extolling the merits of “win-win” cooperation and the importance of “forging a new form of international relations.”

Much of that language disappeared before Friday’s vote as Japan and Western governments pushed back and Chinese diplomats accepted amendments.

But language that remained could still weaken the fundamental principles of international law and practice, and pose a lasting obstacle to the promotion and protection of human rights, Valentin Zellweger, Switzerland’s ambassador, warned the council.

The resolution focuses on cooperation between states, he said, and lacked any balancing reference to the rights of individuals, the role of civil society groups or the mandate of the Human Rights Council to monitor abuses.

It’s an approach backed by other governments on the defensive over their rights records. Initial co-sponsors of the resolution included Syria, Egypt, Myanmar, Venezuela, Burundi, Cambodia and Eritrea.

China itself, Mr. Fisher noted, had repeatedly taken reprisals against rights activists who tried to engage with the United Nations on its record, and had not cooperated with United Nations mechanisms monitoring civil and political rights.

A reminder of how harshly China can approach human rights issues came on Friday when five United Nations experts expressed alarm over the deteriorating health of Jiang Tianyong, a prominent lawyer whose defense of other activists earned him a two-year prison sentence in November on incitement charges.

Mr. Jiang was reportedly weak, they said, and suffering severe memory loss, raising fears that he might have been drugged, tortured or ill treated in detention.

“Their interest is to promote their system and their system is not in accordance with universal human rights, so they are using every opportunity to distort human rights to protect their system,” said Mr. Piccone, of the Brookings Institution. “That’s the ideological battle we are entering into in a whole new way.”